As many as 50 young people in B.C. are diagnosed each year with a heart condition known as sudden unexpected death syndrome, doctors say.

And too many young people are struck dead without knowing anything about the condition -- or how to prevent it, says Dr. Shubhayan Sanatani of the B.C. Children's Hospital.

"The common denominator in almost all cases is an arrhythmia or an irregular heart rhythm," said Dr. Sanatani. "It could be someone at the peak of their fitness, feels nothing, and then has an event.

There are many aspects to the condition but generally it has to do with an undiagnosed heart problem, he said.

One type is Long QT syndrome -- where a slowing of one part of the heart's rhythm can result in a sudden heart attack during exercise.

The condition is rare -- but when it kills it is a tragedy.

Coaches suspect that SFU quarterback Bernd Dittrich had an undiagnosed heart condition that killed him while he was training in the pool last year.

Doctors say Long QT syndrome might be behind the collapse of a 15-year-old, David Badger, in a North Vancouver gym class in 2005.

And the family of 17-year-old Peyman Seyed-Zavari is still struggling with his death in 2006 at Pinetree Secondary's football field in Coquitlam.

"I had no idea, nobody told me what happened," said his Peyman's mother, Frouz Seyed-Zavari. "He was just running and then he fell down. In two minutes, he was gone."

The family remembers Peyman every year as a confident young man who was very sportive and quick with a joke.

"I really miss him," said his brother, Ahmad Seyed-Zavari. "He was a great brother to have."

B.C.'s minister of healthy living told CTV News that she thinks families need to know the risks of the condition.

"It comes down to education and looking at signs and symptoms that may appear out of the ordinary," said Healthy Living Minister Ida Chong.

Signs include fainting during physical activity or chest pains. The condition is usually genetic, so one risk factor is having family members who have suddenly died or who also had a heart condition.

The Seyed-Zavaris were tested -- and found they were negative. They say everyone who has the risk factors should get tested as well.

With a report from CTV British Columbia's Jon Woodward